Dwarf galaxies
NGC 147
(left) and
NGC 185
stand side by side in this deep telescopic portrait.
The two are not-often-imaged satellite galaxies of M31, the
great spiral Andromeda Galaxy,
some 2.5 million light-years away.
Their separation on the sky, less than one degree across a pretty
field of view toward the constellation Cassiopeia,
translates to only about 35 thousand light-years at
Andromeda's distance, but Andromeda itself is found well outside this frame.
Brighter and more famous satellite galaxies of Andromeda,
M32 and M110, are
seen much closer to the great spiral.
NGC
147 and NGC 185
have been identified as binary galaxies, forming
a gravitationally stable binary system.
But recently discovered faint
dwarf galaxy Cassiopeia II
also seems to
be part of their system, forming a gravitationally bound group
within Andromeda's intriguing population of small
satellite galaxies.